Francesco Melzi, a pupil of Da Vinci, received many manuscripts as an inheritance from his master. After Melzi passed away, the documents were lost or scattered. Some got stolen, while others had been given away or misplaced by Melzi. The ones we have today contain just about a fifth of Da Vinci's whole body of work.

The 137-carat yellow Florentine Diamond most likely originated in India and arrived in Europe around the end of the 15th century. Charles I, the last emperor of Austria-Hungary, gave it to Bruno Steiner, an Austrian attorney, to assist the exiled royal family in selling it. What transpired after it is unknown and the diamond is considered lost.

While on a voyage to Mount Everest, George Mallory and Andrew Irvine disappeared, and with them — a camera. The body of George Mallory was found in 1999, while Irvine's body is still missing (allegedly). It is still a mystery if both explorers were able to reach the summit before passing away. If the camera is found, perhaps we could get the answers we seek.

The gold-plated Amber Room, built in the 18th century, was located at the Catherine Palace at Tsarskoe Selo, not too far from St. Petersburg. The room's panels and artwork were torn apart and transported to Germany during 1941. Since then, the room was never put together with original parts, only with replicas.

A fresco by Leonardo da Vinci from 1505 shows Milan defeating the Italian League under Florence at the Battle of Anghiari in 1440. When architect and painter Giorgio Vasari remodeled the hall in 1563, it was gone. Numerous scientists think that Vasari's artwork covers up the Da Vinci mural. Some historians state, that Da Vinci never got around to create the Battle of Anghiari mural.

The smallest of the three pyramids built at Giza around 4,500 years ago is the Menkaure pyramid, named after the Egyptian king. When exploring the pyramid in the 1830s, the Sarcophagus Of Menkaure was uncovered, but when it was transported to Britain, the ship was supposedly destroyed by a severe storm.

Amelia Earhart made history by being the first woman to fly across the Atlantic Ocean and the first person to travel from continental United States to Hawaii. While trying to circumnavigate the whole globe, she disappeared over the Pacific Ocean. It is still unknown what happened to her and where her body is.

The name "Jack the Ripper" came from a letter written by someone claiming to be the infamous serial killer. However, the letter addressed "From Hell" is genuine. The letter arrived with half of a kidney when it was sent to George Lusk on October 15, 1888. The letters were misplaced, thus extinguishing one more lead that could have helped solve the mystery.

Alexander's library might have had the biggest collection of works in the world. It included more than 500,000 ancient texts from Assyria, Egypt, Greece, India, and Persia. Although the blame for destroying the Library falls on fire, the actual cause is unknown. Some claim the Romans destroyed it, while others attribute it to religious motives.

These jewels were created in 1783 with a total of 394 stones. The origins of the stones varied, with some coming from Turkey and Mughal rulers. They were stolen from Dublin castle in 1907. It is unknown who stole them, but some believe it was Francis Shackleton, brother of Ernest Shackleton.

Polish Princess Izabela Czartoryska assembled the "royal casket," or collection of items from the former ruling royal dynasties, in 1800. It contained jewels of the royal family and other riches. The royal coffin was taken by Nazi Germany after it invaded Poland in September 1939. The contents of the coffin are now gone.

Italian painter Michelangelo Merisi da Caravaggio, who worked from 1571 to 1610, produced the Nativity with St. Francis and St. Lawrence in 1609. The picture got stolen from a chapel in Palermo, Sicily, Italy, in 1969, and it's still unknown who took it. A replica was created and unveiled in 2015.

The trophy was initially given out at the first World Cup in 1930 and was handed from one champion to another every four years. After Brazil won the competition for the third time in 1970, they were given the trophy and allowed to keep it. Unfortunately, the cup was stolen in 1983 and disappeared from the public eye.

The 1906 Australian movie Story of the Kelly Gang was the first full-length motion picture ever made. The movie gained considerable prominence due to rising crimes. More criminal activity increased in the neighborhood as a result. Sadly, it was never correctly saved. A portion of it was made public thanks to fragment discoveries.

Chaucer only completed writing roughly a fourth of the stories (24 of the 100, to be exact) he intended to include before passing away. Some of those stories were still in pieces when he passed away. Since there are a lot of variations of the stories, it is not clear how the original narrative should go.

This magnificent tapestry, 230 feet long and 165 feet tall, was created in the 11th century. The Norman conquest of England was displayed on it. The tapestry was split up in 1792 and used as a military resource to cover up wagons. When historians tried to put it together, parts were missing, thus a narrative couldn’t be completely assembled.

Nazi authorities seized the Portrait of a Young Man artwork from a gallery, wanting to display it in the planned Linz Art Gallery. The picture was last spotted in Hans Frank's cottage in Neuhaus on the shore of Lake Schliersee, Germany, in January 1945. No one knows the whereabouts of this artwork.

The Italian artist Michelangelo di Lodovico Buonarroti Simoni created the marble sculpture "Mask of a Faun," which has half-human and half-goat characteristics. When German forces took it from Castello di Poppi, a fortress in Tuscany, in 1944, it was misplaced and disappeared. The mask's current location is unclear.

The old mythological event where the god Jupiter seduces Leda, the queen of Sparta, is shown in Michaelangelo's work Leda and the Swan. Although it is unknown precisely how Michelangelo's picture disappeared, one theory is that at some point in the last 500 years, some people found its sexual content too much and destroyed it.

The Hebrew Bible describes the Ark of the Covenant as a chest with tablets bearing the 10 Commandments. The chest was stored in a Jerusalem temple that was allegedly constructed by King Solomon. The fate of the Ark of the Covenant is unknown (unless you saw Indiana Jones), and information about its whereabouts have long been lost.

The Russian jeweler Peter Carl Fabergé, from 1885 to 1916, produced elaborately designed "Easter eggs" for the Russian imperial family. Sadly, several royal family members got taken out during the Russian Revolution, and some eggs were lost and erased from history. The ones that are secured are worth quite a lot of money.

According to folklore, a Nazi unit under SS leader Ernst Kaltenbrunner submerged a significant amount of money into Lake Toplitz in Austria after World War II. It was done to prevent it from falling into the hands of eastern armies. Numerous searches have been conducted, but no gold has yet been discovered.

The Honjo Masamune is a sword that many believe was made by Gor Nyd Masamune, regarded as the greatest swordsmith in Japanese history, who lived from 1264 to 1343. It was taken by the US occupying forces and then swiftly vanished. American troops probably destroyed the sword with many other Japanese weapons.

The city of Nimrud was captured in June 2014 and looted by the Islamic State, a terrorist group. Recaptured in 2016, it was time to count the stolen and destroyed items. Many of the valuables of Nimrud were lost forever, while others were damaged. Some of the loot got sold on the black market.

Completed in 1408, the Yongle Encyclopedia was the biggest in China and the globe. It got transferred to the Forbidden City around the 1500s for security. The original was lost or dispersed shortly after the emperor had it reproduced. Some historians think a fire that engulfed the Forbidden City during a revolt destroyed the Yongle Encyclopedia.

The Colossus, one of the Seven Wonders of the Ancient World, was modeled after the Greek sun deity Helios. It was built around 280 B.C, but a part of it got destroyed in a devastating earthquake that hit Rhodes in 226 B.C. Parts of the statue are still intact, unlike the remains of other antique artifacts.

The Greek lyric poet Sappho flourished in the seventh century B.C. Unfortunately, very few of her poems have survived the test of time. In 2014, University of Oxford specialist Dirk Obbink made portions of two previously undiscovered Sappho poems public. Locations of other works are unknown.

The "Just Judges" panel is a component of the 15th-century Ghent Altarpiece, a piece of art located in Saint Bavo's Cathedral in Ghent, Belgium. It was created by Hubert and Jan van Eyck. The panel disappeared in 1934 and has been lost ever since. Nevertheless, despite the passing of time, new information keeps coming in, and the case file is still open.

The majority of scholars concur that Thomas Kyd's play Ur-Hamlet served as the inspiration for Shakespeare's well-known tragedy. Sadly, there are no copies of Ur-Hamlet left for us to enjoy. The only thing known is that Ur-Hamlet played in London, adding to the theory that William Shakespeare saw the play and got inspired to write his own Hamlet.

The text carved on a sheet of copper that describes the location of a large amount of hidden wealth might be the most remarkable Dead Sea Scroll found in the Qumran caves in the West Bank. According to some academics, the wealth mentioned in the Copper Scroll might be the one that was hidden from the approaching Roman soldiers.

Two shady burglars from Boston, Massachusetts, stole 13 items of art worth over $500 million. Rembrandt, a Dutch painter, contributed three of them, while Edgar Degas, a French artist, contributed five. The identity of the burglars is still a mystery, and the works of art were never found.

The Mexican revolutionary commander Francisco "Pancho" Villa was portrayed in the lost movie The Life of General Villa. Although it was made and shown, it is now gone. Shortly after the movie's debut, Villa's men invaded New Mexico and massacred several Americans, turning him into an enemy of the United States.

The gold-plated Parliamentary Mace symbolizes the Speaker's office and the people's constitutional rights. One of Australia's biggest mysteries is the theft of it from Victoria's Parliament. However, anyone who locates the mace today and returns it will get a hefty $50,000 prize.

Plato is known for many things, one of which is his Hermocrates - an end to a three part story. The texts are full of monologues and writings in the first person. What was written is left up to historians to speculate. The speaker might have been a Syracusan general and statesman. It might have provided insight into naval strategy and power.

You might have read Hamlet, but did you know about Love’s Labour’s Won, the lost William Shakespeare creation? Some academics contend that references to Love Labour's Won alludes to Shakespeare's well-known and often staged comedy Much Ado About Nothing. This work does not appear to have any surviving copies.

The Roman troops took the Second Temple's riches back to ancient Rome before it got destroyed. These riches included the menorah, a six-branched light stand. The menorah is large, almost like the soldiers carrying it. It's unknown what happened to the menorah once it arrived in Rome.

Because it was the cup that Jesus drank from or used to serve wine at the Last Supper, the Holy Chalice has been a subject of many adventures. It is linked to the Holy Grail, a mythical object from Arthurian mythology. To this day, scholars continue to disagree on the Holy Chalice's existence and location.

The remains of a hominid, known as Peking Man, found in a cave in 1923, could have shone some light on the history of humanity. However, the fossils vanished in 1941, during the Japanese invasion of China, and it is still unclear where they are. The fossils may have gotten lost at sea during their journey to the United States, who were trying to rescue them.

Even today, thrill-seekers and treasure hunters risk their lives and health to find the hidden treasure of the “Dutchman” in Apache Junction. The “Dutchman”, a German immigrant named Jacob Waltz, hid some gold in the mountains and took the location of it with him to the grave. Some believe that the trove is full of precious metals. 

Modern academics refer to the Q Source, or just Q, as a fictitious first-century A.D. document that includes some quotations ascribed to Jesus. The fact that some sections in Matthew and Luke are similar builds the foundation for Q Source. Sadly, this is only theoretically possible because of the lack of evidence.

The canonical Christian gospels of Mark, Luke, Matthew, and John are available in manuscript form from the second century A.D. However, academic experts think that several of these gospels were first composed in the first century. It is still a mystery if the first draft versions of the stories are still around.